Field of the Invention
The invention relates to a method for the production of blanks for sintered glass bodies for glass seals, in which a number of layers are arranged one above the other in a 3D printing process, wherein in a first step, a first layer of a glass powder is spread on a surface, a computer-controlled stream of a printing fluid is directed to selected areas of the first layer in a pattern prescribed by the computer, in a second step, a further layer of the glass powder is spread over the first layer and on it, a computer-controlled stream of printing fluid is directed in a pattern prescribed by the computer to selected surfaces of the second layer and the two steps are repeated until the blank is formed.
Description of the Background Art
Blanks for sintered glass bodies for glass seals are typically understood to be bodies which through sintering produce a glass body needed for sealing. Such glass bodies are needed in particular for glass seals, in which metallic conductors are secured by glass fuse seals or glass solder in a metal outer body. It may be necessary to produce accurate glass body structures with more than 100 sealed inner conductors.
With the known methods, the glass bodies are produced by a printing method in which a glass granulate offset with a binding agent is printed to form a blank for sintered glass bodies with tools specially prepared for this mold. The production of such tools entails high costs and long development times. Furthermore, only certain geometric shapes can be produced.
For special and high-precision production of complex components, 3D printing is increasingly used.
From U.S. Pat. No. 5,204,055 A it is already known to provide 3D printing methods for the production of workpieces with powder as a raw material, wherein a plurality of layers is stacked from the bottom up.
Further, in DE 11 2005 002 040 T5, which corresponds to U.S. Pat. No. 7,141,207, a method for the production of articles made of aluminum and magnesium is described. Prototypes for automotive parts are manufactured therewith.
WO 2014/067990 A1 describes a method for producing a ceramic green body in which on a substrate, a layer is formed that contains a ceramic, glass ceramic or glass powder. A hardening composition with a solvent or dispersing agent is applied to a part of the layer. These steps are repeated at least once, removing the solvent or dispersant partially or completely by forming a green body. The unbound ceramic powder is also removed, leaving the green body exposed.
Glass seals must meet specific requirements, in particular a low porosity, that are not achieved with the known methods.